Excimer Laser Patterned Holey Graphene Oxide Films for Nonenzymatic Electrochemical Sensing
Excimer Laser Patterned Holey Graphene Oxide Films for Nonenzymatic Electrochemical Sensing
复制标题
DOI：
10.1021/acsami.2c09096
复制
发表时间：
2022-08-17
影响因子：
9.5
通讯作者：
Narayan, Roger
中科院分区：
文献类型：
--
作者：
Joshi, Pratik;Shukla, Shubhangi;Narayan, Roger
点缺陷、孔和波纹（宏观缺陷）的存在在石墨烯及其衍生物中诱导高催化潜力。我们报告了一种系统的方法，通过改变激光能量密度和脉冲数，以实现7.15 nM的记录检测限过氧化物传感的准分子激光诱导还原氧化石墨烯的微观和宏观缺陷密度优化。使用拉曼光谱获得点缺陷密度的定量估计，并与电化学传感测量确认。在0.6 J cm（-2）下的激光退火（LA）导致通过存在悬挂键的熔融碳的液相再生长形成高度还原的氧化石墨烯（GO），使其具有催化活性。霍尔效应测量产生的迁移率类似于2.00 cm（2）V-1 s（-1）。在0.6 J cm（-2）下脉冲数量的额外增加导致通过固态途径脱氧，导致多孔石墨烯结构的形成。平均孔尺寸显示出分层的增加，与脉冲的数量，其特征在于与多种显微镜技术，包括扫描电子显微镜，原子力显微镜，和透射电子显微镜。10个脉冲后由于高空穴密度而导致的边缘位点的暴露支持近端扩散层的形成，这导致容易的质量转移和过氧化物感测的检测限从25.4 mM提高到7.15 nM。然而，在1 J cm（-2）和1个脉冲下的LA导致熔融碳的高熔融寿命和GO的形成，其特征在于3 × 10（-2）Ω-cm的高电阻率，这对于感测应用来说并不理想。使用间歇式炉的快速热退火技术产生多孔石墨烯导致具有不均匀孔尺寸的结构。然而，使用LA技术的多孔石墨烯形成是可扩展的，具有对孔尺寸和密度的更好控制。这项研究将为先进传感应用的成本效益和高性能多孔石墨烯传感器铺平道路。
The existence of point defects, holes, and corrugations (macroscopic defects) induces high catalytic potential in graphene and its derivatives. We report a systematic approach for microscopic and macroscopic defect density optimization in excimer laser-induced reduced graphene oxide by varying the laser energy density and pulse number to achieve a record detection limit of 7.15 nM for peroxide sensing. A quantitative estimation of point defect densities was obtained using Raman spectroscopy and confirmed with electrochemical sensing measurements. Laser annealing (LA) at 0.6 J cm(-2) led to the formation of highly reduced graphene oxide (GO) by liquid-phase regrowth of molten carbon with the presence of dangling bonds, making it catalytically active. Hall-effect measurements yielded a mobility of similar to 2.00 cm(2) V-1 s(-1). An additional increase in the number of pulses at 0.6 J cm(-2) resulted in deoxygenation through the solid-state route, leading to the formation of holey graphene structure. The average hole size showed a hierarchical increase, with the number of pulses characterized with multiple microscopy techniques, including scanning electron microscopy, atomic force microscopy, and transmission electron microscopy. The exposure of edge sites due to high hole density after 10 pulses supported the formation of proximal diffusion layers, which led to facile mass transfer and improvement in the detection limit from 25.4 mM to 7.15 nM for peroxide sensing. However, LA at 1 J cm(-2) with 1 pulse resulted in a high melt lifetime of molten carbon and the formation of GO characterized by a high resistivity of 3 x 10(-2) Omega-cm, which was not ideal for sensing applications. The rapid thermal annealing technique using a batch furnace to generate holey graphene results in structure with uneven hole sizes. However, holey graphene formation using the LA technique is scalable with better control over hole size and density. This study will pave the path for cost-efficient and high-performance holey graphene sensors for advanced sensing applications.